WEB Comparative studies of two different sized inkjet nozzles for several bioinks based on alginate
Emine Karakaya, Faina Bider, Andreas Frank, Stefan Schrüfer, Aldo R. Boccaccini, Hans-W. Schmidt, Dirk Schubert, Rainer Detsch.
Inkjet printing of living cells is a biofabrication technology which is used for pharmaceutical, biological and medical purposes. In this regard, the precision of printed constructs is crucial and can be determined by parameters e.g. current, pressure, nozzle size and the choice of bioink. Sodium alginate based bioinks are widely used for biofabrication approaches due to a high biocompatibility, comparative low cost and tunable properties.
Therefore, the aim of this study, is to evaluate suitable bioinks based on sodium alginate and determine optimal parameters for two nozzle diameters resulting in highly precise prints with high cell viabilities.
For this purpose, all bioinks were firstly rheological investigated to determine the most suitable concentration and viscosity for inkjet printing. The printability of all materials was anlayzed using two different nozzles (100 µm and 300 µm). Influences of parameters e.g. current, size and pressure on the droplet formation were investigated and optimal parameters for highly precise printing results were determined. Moreover, we embedded NIH3T3 cells into all bioinks (1 Mio/mL) and printed these with the determined optimal parameters, respectively. The cell vitality was analyzed after 24 h of incubation using the software ImageJ.
In summary, printing resolutions depending on current, pressure, nozzle size and bioink were evaluated. It was found out that the inkjet printing process using alginate based hydrogels led to completely programmable, accurate and high precise printing resolutions for both nozzles sizes. Furthermore, the biological suitability of alginate based hydrogels were proven by high cell viabilities in the printed constructs.